How to score 2-for-1 tacos and/or 2-for-1 airfares: - Download a free Loopt Star iPhone app here or here. Loopt Star allows you to check in at participating bars, shops, and restaurants to score discounts and exclusives- In San Francisco, anytime between 11 am and 3 pm PST, head to the the Los Compadres taco truck parked at 100 Folsom Street, find the Virgin America people, and check in on Loopt Star- In Los Angeles, between 11 am and 3 pm PST, head to 7060 Hollywood Boulevard, find the Virgin Atlantic employees at the Border Grill taco truck, and check in on Loopt Star.- Get your tacos and tickets!- If you’re at the airports, just check-in with Loopt Star. No tacos, alas, but the airfare special will save you enough for lots and lots of tacos when you arrive south of the border

Where do the Chihuahuas come in? Proceeds from every taco sold today go to the Chihuahua rescue efforts of the San Francisco Animal Care and Control. (Remember the big Chihuahua airlift that Virgin America participated in last fall?)